Plastic container base



FIG. 1 is a top, front and left side perspective view of a plastic container base showing our new design;

FIG. 2 is a bottom, left side and front perspective view thereof;

FIG. 3 is a front elevation view thereof;

FIG. 4 is a rear elevation view thereof;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is a right side elevation view thereof; and,

FIG. 8 is a left side elevation view thereof.

The broken lines shown in the drawings are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a plastic container base, as shown and described. 